1. Field of the Invention
The present invention relates to a prime mover output control system for a power-generating system in which, by means of a prime mover such as a water turbine, a steam turbine, a gas turbine, or an engine, a generator is rotated to generate electric power.
2. Description of the Related Art
In a conventional control system for prime mover output (mechanical) torque, there has been a problem in that, because a rotating speed detection signal includes white noise, such as sensor noise, and colored noise due to precession movement of a generator, whereby a signal is always outputted, a control system for prime mover output (mechanical) torque operates; therefore, in order to eliminate these types of noise, limitation of output, a dead band, and a band-pass filter are provided (e.g., Japanese Laid-Open Patent Publication No. 2002-233195, Paragraphs 0017 through 0025, FIG. 1).
In addition, there has been a conventional control system (e.g., Japanese Laid-Open Patent Publication No. 1996-266095, Paragraphs 0021 through 0028, FIG. 1) in which a dead-time function receives the deviation between a generator-output command signal and a generator-output signal, determines hunting status, and adds up a difference signal and the output of the dead-time function so as to make a control signal zero.